Bronchiectasis

Jonathan H. Chung, MD

DIFFERENTIAL DIAGNOSIS

Common

Postinfectious
- Mycobacterium Tuberculosis
- Mycobacterial Avium Complex
- Swyer-James (MacLeod) Syndrome
- Aspiration (Recurrent)
Postobstructive
- Endobronchial Tumor
- Lymphadenopathy
- Foreign Body
Traction Bronchiectasis
Cystic Fibrosis
Asthma

Less Common

Allergic Bronchopulmonary Aspergillosis
Immotile Cilia Syndrome
Immunosuppression
- Congenital
- AIDS

Rare but Important

Williams-Campbell Syndrome
Tracheobronchomegaly (Mounier-Kuhn Syndrome)
Young Syndrome
Yellow-Nail Syndrome

ESSENTIAL INFORMATION

Key Differential Diagnosis Issues

Definition: Pathologic, irreversible dilation of bronchi

Helpful Clues for Common Diagnoses

Postinfectious
- Mycobacterium Tuberculosis
  - Upper lung bronchiectasis
  - Signs of previous tuberculosis: Upper lung fibrocavitary disease, calcified lymph nodes, calcified granulomas
  - Low-attenuation lymphadenopathy, tree in bud or miliary nodules, or cavitary lung disease in active disease
- Mycobacterial Avium Complex
  - Most common in older women
  - Cylindrical bronchiectasis most severe in middle lobe and lingula
  - Tree in bud nodules, larger random nodules (occasionally cavitate)
  - In minority of cases, mimics upper lung fibrocavitary disease of reactivation tuberculosis
- Swyer-James (MacLeod) Syndrome
  - Due to childhood pneumonia (adenovirus, measles, Mycoplasma, pertussis)
  - Bilateral but asymmetric process; usually more involvement of 1 lung
  - Unilateral hyperlucency of more affected lung: Hypoplasia of pulmonary vasculature and constrictive bronchiolitis
  - Small to normal size of more affected lung
- Aspiration (Recurrent)
  - Predisposition in patients with neuromuscular disorders or esophageal abnormalities
  - Dependent portions of lungs: Superior and basilar segments of lower lobes (right greater than left)
Postobstructive
- Endobronchial Tumor
  - Squamous cell carcinoma in older patients with history of smoking
  - Carcinoid tumor in young patients; often low activity on FDG PET
- Lymphadenopathy
  - Chronic extrinsic compression of bronchi
  - A cause of middle lobe syndrome: Chronic atelectasis and bronchiectasis in middle lobe or lingula
- Foreign Body
  - Abnormal fixed hyperinflation > atelectasis of lung or lobe even with expiration or lateral decubitus positioning
  - Direct visualization of foreign body (CT > radiographs)
Traction Bronchiectasis
- Concomitant end-stage lung disease or pulmonary fibrosis, radiation fibrosis
- Reticular opacities, interlobular septal thickening, architectural distortion, honeycombing
Cystic Fibrosis
- Upper lung bronchiectasis; air-trapping; tree in bud opacities &/or centrilobular nodules
- Fatty atrophy of pancreas
Asthma
- Mild cylindrical bronchiectasis with patchy regions of air-trapping and bronchial wall thickening

Helpful Clues for Less Common Diagnoses

Allergic Bronchopulmonary Aspergillosis
- Central cystic bronchiectasis and severe mucus plugging or air-fluid levels in asthmatic
Immotile Cilia Syndrome
- Middle and lower lobe bronchiectasis, situs inversus/dextrocardiac in 50%, paranasal sinusitis, male infertility
Immunosuppression
- Congenital
  - e.g., primary impaired cellular or humoral immunity, infantile X-linked agammaglobulinemia
  - Bronchiectasis secondary to recurrent infection
  - Hypogammaglobulinemia: Lower lung preponderance, severe bronchial wall thickening
  - Common variable immune deficiency syndrome: Concomitant reticular opacities
- AIDS
  - Likely secondary to recurrent bacterial infection; lower lobe preponderance; air-trapping

Helpful Clues for Rare Diagnoses

Williams-Campbell Syndrome
- Defective cartilage in 4th to 6th order bronchi
- Central cystic bronchiectasis; collapse with expiration and dilation with inspiration
Tracheobronchomegaly (Mounier-Kuhn Syndrome)
- Dilation of trachea and main bronchi; tracheal diverticula along posterior aspect of trachea; ± tracheomalacia
- Central cystic bronchiectasis
Young Syndrome
- Resembles immotile cilia syndrome: Paranasal sinusitis, bronchiectasis, male infertility
Yellow-Nail Syndrome
- Bronchiectasis in setting of abnormally thick, discolored nails; exudative pleural effusions; lymphedema

Alternative Differential Approaches

Unilateral bronchiectasis
- Post-primary tuberculosis
- Bronchial stenosis: Bronchial atresia, postinfectious, sarcoidosis
- Obstructing endobronchial tumor
- Foreign body
Bilateral or diffuse bronchiectasis
- Congenital: Cystic fibrosis, immotile cilia syndrome, congenital immunodeficiency
- Infection: Recurrent aspiration, post-viral, allergic bronchopulmonary aspergillosis
- Traction bronchiectasis

Image Gallery

Axial CECT shows right upper lobe bronchiectasis

with adjacent consolidation

and bilateral small nodular opacities

in this patient with active mycobacterial tuberculosis infection.

Axial NECT in this elderly woman shows mild bronchiectasis

in the right middle lobe and lingula; there is associated volume loss suggested by anterior displacement of the major fissures

(Left) Axial NECT shows bronchiectasis, paucity of vessels, and decreased density of the left lung, consistent with Swyer-James (MacLeod) syndrome. The patient had a history of a severe childhood respiratory infection. (Right) Axial NECT shows left lower lobe patchy centrilobular opacities